Workpiece holder



Nov. 5,4 1957 G. ERICSSON WORKPIECE HOLDER Filed April 4, 1955 2Sheets-Sheet 1 ffii Nov. 5, 1957 G. ERlcssoN woRxPIEcE HOLDER 2Sheets-Sheet 2 Filed April 4, 1955 my@ A@ g MAI.

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232 IN V EN TOR.

nited States Patent 2,811,771 WoRKPIE-CEHOLDER Gustav Ericsson, Kenmore,NaAY. .Appneatipnrsprnlaf S1955, senarNo. 498,832 f claims. ,(cl.90m-ss) .workpiece is `assured of parallelismi with a surface on theholder.

Another Objectis to provide such a combination clamp and parallelworkpiece holder which can be quickly adjrusted to', permit-.the`-wovrkpiecetobe removed and an- /other workpieceY readilysubstitutedwithout-y throwing the v setup out vof square.

Another Objectis to, provide. such a holderwhich is relatively simple inconstruction, inexpensive toy manufacture, y easy to operate andadaptable for holding a wide variety of sizes of workpieces.

Other objects and advantages ofthe present invention will be apparentfrom .thedescrip,tion and accompanying drawings in which:

i Fig. 1 is a-sidefelevational view of a holder embodying one form ofthepresent invention and showing aworkpiece arranged `thereon but vwithclamping .devices not adjusted so as to firmly clamp such workpiece.

Fig. 2 ,is a top elevational view of the holder and workpiece shown inFig. l.

Fig. 3 is an enlarged fragmentary verticalsectionall view ofthe righthand portion of the holder shown in I Figs. 1 and 2, this view beingtaken on line 3 3, Fig. 2. Fig. 4 is a view similar to Fig. 3 but of as'till'lmore fragmentary nature and showing one of the clamping devicesarranged in an operative or clamped position.

Fig. 5 is a vertical transverse sectional view thereof taken on line 55, Fig. 3.

Fig. 6 is a fragmentary horizontal sectional view thereof taken on line6 6, Fig. 3.

Fig. 7 is a side elevational view embodying another form of the presentinvention andl showing the clamping devices in an inoperativenconditionwithl respect to the workpiece. i I

Fig. 8 is a vertical transverse sectional view thereof taken on line 88, Fig. 7. y

Fig. 9 is atop elevational view of still a further embodiment of thepresent invention.

Fig. l0 is a verticaltransverse sectional view thereof taken on 1ine 1010, Fig. 9.

Fig. l1 is a fragmentary vertical longitudinal section through the righthand clamping device shown in Fig. 9, this View being taken on line.1112 l thereof .and .showring` the clamping device in operative `conditionwhereas v.the same Adevice is"i1lustrrated4 in .aniinoperative conditioninEFig. 7.

y Referring to Figs. `1*-6. lembodying,oneQform lof `the i presentinvention, the numeral represents generally an elongated base havingparallelupp'er 'and lowerhorizontal flat surfaces 21 and 22respectively. Asabest shown in Fig. 5, the base1 20 isgen'era1ly,chan11el,shapedfin V.crossjsection,.openping to its uppersurface Z1 yValid, .having a `bottom wal1' 23 ,and transversely,'spacedf,.upstariding `side walls 24, 24. The .innensurface'ofeach'of'the'sidelwalls 2,4"is14 shown as'provided with a.longitudinally extending horizontal grcove.25."` The .bottom walli23isisliown as having a pair of longitudinally alined elongatedislts 27,

through which suitable fasteners (not shown) may extendfor holding thebase tothe machine tool.

AAdapted to,be placedon the flat upper surface 21 of Athewbase 20 is aworkpiece represented by theletter W. Such workpiece is shown as a blockhaving a at bottom surface engaging the upper at surface 21 and parallelvertical side walls. It is the purpose ofthe present in- `ventiontoclamp such workpiece W to such surface 21 insuch manner that theseengaging surfaces are in f ull contact and are not cocked relative toeach other. Such .cooking is common with holders as presentlyconstructed and occurs when clamping on opposite sides of the workipiece` are forced toward each other.

Inaccordance with the present invention, aA clamping `d eviceindicatedgenerally at 26 isv arranged on the base 20 on `each ofthe oppositesides of the workpiece W. These` clamping devices 26 are shown as` beingidentical in construction except that one is reversely arranged withVrespect to the other and hence a detailed description of .onesuchclamping device will suiiice for both.

Referring to Fig. 3 in whichthe right hand clamping device 26 isillustrated in section, such. device is shown as including a support 28.Suchsupport. is in the form '.of a .rectangular flat block orplate'adapted toV be, moved vlongitudinallyof the opposing groovesarranged in the side walls 24 ofthe base 20. The inner end of the sup-Vport orxslide 28 is.shown as beingcut out so as to leave a pairoftransversely spaced ears` 29 which-'projection wardly and horizontally.Each of these' ears 29 is provided with a central hole and these holesare alignedwith eachother so that a pivot pin 30 can be arranged`therein as shownin Fig; 5. The `intermediate portion of this pivot pin30 extends through a hole' provided in the depending portion31 of a bodymember 32 arranged 1vabove the slide 28. This body lmember 32 iss hownas having an integral upstanding part 33 which in planview is ofrectangular shapewith its side walls spaced inwardly of thecorrespondingsides of the body member 32.. The

iupstanding part 33 has a transverse hole adjacent its outer or rear endwhich receives a pivot pinV 34. The outer` ends of the horizontaltransverse pivot pinv 34 ex- Vtend outwardly beyond the correspondingside ofthe up- "standing part 33 ,and on such extremities areV arrangedthe free ends of a U-shaped jaw member 35 having a pair'of outwardlyextending horizontal .arms`36` which are transversely spaced from eachother` and embrace the s ides of the upstanding part 33. The crossv partof the rLiv-shaped jaw member is arranged on ,the inner side of theupstanding part 33 and this cross partis sufficiently spaced from theinner end of theupstanding part 33 so a to permit some relative movementtherebetween about the axis ofthe pivot pin 34.

AThe Ufshaped jaw member 35 is urged upwardly relative` tothe upstandingpart 33 by a helical compression spring 38 arranged with its axisvertical and having its lower portion arranged in a recess 39V providedinthe `body member 32 at its inner end and immediately above theldepending part 31. The upper end of the 4spring 38 bears against thebottoni of thecross vpart of the U-shaped jaw` member 35. In order tolimit the upward movement ofthe jaw member 35 relative to the bodymember 32, l `the, jaw member is shown as carrying a transverse, cylin-`drical, horizontal rod 40 which is anchored at its ends in any suitablemanner on the arms 36. This transverse rod 40 extends through anenlarged transverse hole 41 in the upstanding part 33. Some relativemovement between the rod 40 and hole 41 is permitted as can be seen .bycomparing Figs. 3 and 4.

The forward or exposed end face 42 of the jaw mem- ,.-.be1135isarcuately cylindrically curved, being generated about a horizontaltransverse axis located below the axis of the transverse pivot pin 34and preferably slightly to the rear thereof. In the drawings, the centerof curvature for the jaw face 42 is at about the corner between the topof the tail of the body member 32 and the vertical rear face of theupstanding part 33.

Referring to Fig. 3, pressure of the jaw face 42 against the verticalend face of the workpiece W engaged thereby will produce a line of forceextending below the pivotal axis of the jaw member 35. This produces atorque on the jaw member tending to rotate it in a counterclockwisedirection relative to the body member 32 as reviewed in Fig. 3. Sincethe work face of the jaw member tends to move downwardly a downwardthrust is imparted to the workpiece.

In order to move the jaw member 35 inwardly toward the workpiece W5means are provided for pivoting the body member 32 about the axis of thepivot pin 30 relative to this body member in a counterclockwisedirection as viewed in Figs. 3 and 4. Such means are shown as comprisinga vertical jack screw 43 which works in a threaded hole provided in thetail part of the body member 32. The lower end of this screw 43 bearsagainst the upper surface of the slide 28. The screw may be turned inany suitable manner and for this purpose, its upper end is shown asprovided with a central out-of-round recess 44 adapted to receive anAllen wrench (not shown).

Means are provided for locking the slide 28 of each clamping device inany desired position longitudinally along the base 20. As shown in Figs.1 4,- such means include providing a series of longitudinally spacedhorizontal holes 4S extending transversely through the slide 28, aseries of longitudinally spaced, transversely extending horizontal holes46 arranged in each side wall 24 of the base 20 opposite the groove 25therein, and a locking pin 48 shown as having an enlarged externallyknurled head at one end to facilitate grasping the same. The series ofholes 45 in the slide 28 are spaced slightly closer together than theseries of holes 46 in the base 20. In this manner, a wide range ofadjustment is permitted between the slide 28 and the base 20 and when apair of holes 46 on opposite sides of the base align with one of theholes 45 in the slide 28, the locking pin 48 can be insertedtherethrough so as to secure the slide against longitudinal movementrelative to the base.

Assuming the locking pin 43 for each clamping device 16 to be removed,the workpiece W is placed with its ilat bottom against the top surface21 of the base 20 and longitudinally of this base so that sufficientroom will remain on either side of the workpiece to accommodate aclamping device 26. The clamping devices are then slid inwardly alongthe guideways 25 until they contact the workpiece W. The locking pins 48are then inserted into the proper set of registered holes 45 and 46.This may actually occur where there is a slight spacing between the workfaces 42 of the jaw members 35 and the workpiece. The parts will then bein the positions shown in Fig. l. Thereafter, each jack screw 43 isturned so as to raise the tail part of the body member 32. This operatesto swing the body member 32 about its pivot pin 30 toward the workpieceW. During such movement, the jaw member 35 of each clamping device willengage the side face of the workpiece and continued turning of the jackscrew 43 will result in relative movement between the jaw member 35 andthe body member 32 about the axis of the pivot pin 34. The jaw memberwill then take the operative position shown in Fig. 4 in which the jawmember has been moved downwardly with respect to the body member againstthe urging of the spring 38 therebetween. It will be understood that thework face 42 of each jaw member will have a rolling movement on the sideface of the workpiece W coupled with horizontal and vertical forcecompartments which result in a combined force which will urge the remotelower corner of the workpiece, or that corner adjacent the otherclamping device 26, downwardly against the upper part 21'of the 4 base20.

piece and the ilat upper surface 21 of the base.

The modified form of the invention shown in Figs. 7- and 8 has only twoessential differences from the form shown in Figs. l-6. One suchdifference is in the manner of limiting the upward movement of the jawmember.-

The other difference is in the mounting of the clamping device on thebase.

As shown in Figs. 7 and 8, the base 201 is channell shaped in crosssection and the outer vertical surfaces of its side walls 241 areprovided with a series of crossed slots 50 and 51. These slots 50 and S1incline at a slight angle with respect to the vertical on opposite sidesthereof. Adapted to be received in such slots are a series of similarlyinclined ribs 52 which are provided on the support 281. This support 281is generally of inverted channel shape in cross section having dependingside walls 53 which embrace the side walls 241 of the base 201. The ribs52 stand out from the inner surfaces of these side walls 53 and arepreferably formed integrally therewith. It will therefore be seen thatone series of slots 50 is used when one of the clamping devices 261 isarranged on one side of the workpiece W and the other series of slots 51used when a similar clamping device 261 is arranged on the opposite sideof the workpiece W. The setting of the support 261 for each clampingdevice with respect to the base 201 is determined by the engagement ofthe ribs 52 with given slots of the series 50 or 51. It will be notedthat the ribs 52 incline upwardly and inwardly with respect to theworkpiece W. In mounting a clamping device 261 on the base 201, thesupport 281 is held above the base and then lowered causing a camsliding action between the slots and the ribs which moves the clampingdevice downwardly and outwardly away from the workpiece W.

Each clamping device 261 is shown as having a body member 321 hinged atits inner end by the pin 301 to thev respective support 281. The bodymember 321 is shown as having a pair of transversely spaced, upstandingintegral extensions 331 between which the jaw member 351 is arranged andpivoted at its outer end on the pivot pin 341. The free end of the jawmember 351 has lateral horizontal extensions 53 to provide an enlargedhead which extends past the inner ends of the upstanding extensions 331on the body member 321. The opposing faces of the lateral jaw extensions53 and the upstanding extensions 331 are inclined as indicated at 54whereby the inclined faces 54 extend upwardly and inwardly toward theworkpiece W. Engagement of these overlapn ping and inclined faces asshown in Fig. 7 operates to limit the upward movement of the jaw member351 under the urging of its respective spring 381. However, the jawmember 351 can move downwardly against this spring 381 to assume aposition with respect to the body member 321 as shown in Fig. 1l.Otherwise than as described above, the form of the invention shown inFigs. 7 and 8 is constructed and operates in the same manner asdescribed for the form of the invention shown in Figs. 1 6.

The further modied form of the invention shown in Figs. 9, 10 and 11 hasa clamping device similar to 261 and hence the same reference numeralsare applied. The only difference is in the mode of attaching theclamping device to the base. Referring to Figs. 9 and 10, the base isshown at 202 having an upper at surface 212. The support for theclamping device is indicated at 282. This support has downwardlyextending side walls 55 along opposite lateral sides thereof andinturned horizontal flanges along their lower edges as indicated at 56.These flanges 56 are slidingly received in external horizontal groovesprovided in the side walls 242 of the base 202. Each marginal portion ofthe support 232 and its cor- When this operation is performed on both`clamping devices 26 successively or simultaneously, it will" be seenthat the workpiece W is firmly held or clampedy to the base 20 in suchmanner that a full surface to surface contact is assured between the atbottom of the work responding inturned flange 56 is provided with aseries of longitudinally spaced vertical holes 58. The portion of eachside wall 242 between the support 282 and the corresponding ange S6 isprovided with a series of longitudinally spaced vertical holes 59. Thespacing between the holes S8 is slightly less than the spacing betweenthe holes 59. In this manner, any one of the holes 58 is adapted to bealigned with the holes 59 and to receive a vertical locking pin 60. Thelocking pin 60 is shown as having an enlarged externally knurled head atits upper end which head facilitates grasping the locking pin forinsertion and removal from the holes. Otherwise, the form of theinvention shown in Figs. 9 and l0 is similar in construction andoperates in the same manner as described for the form of the inventionshown in Figs. 7 and 8.

From the foregoing, it will be seen that the present invention providesa parallel and workpiece holder which includes clamping devices whichsecurely hold the workpiece on the upper flat surface on the base of theholder. Once a given longitudinal setting of the clamping devices hasbeen made on the base, the workpiece can be changed rapidly and easilyby loosening a pair of jack screws which form a part of the clampingdevices. Further, the holder of the invention assures each workpiecebeing held in a proper position during machining operations thereonwithout requiring a time consuming original setup operation each timethe workpiece is changed. Obviously, the invention has great value wherethe same machining operation is performed on a succession of identicalworkpieces. By reducing setup time for each workpiece, as achieved bythe present invention, a high rate of production can result.

I claim:

1. A holder for a workpiece, comprising a base on which said workpieceis adapted to be placed, and a pair of clamping devices mounted on saidbase and adapted to be arranged one on each of opposite sides of saidworkpiece, each of said clamping devices comprising a support arrangedfor immovable connection to said base, a body member pivotally mountedon said support about a transverse axis arranged adjacent its front end,a jaw member having a curved work face at its front end adapted toengage said workpiece and pivotally mounted on said body member about atransverse axis arranged in rear of said first mentioned axis, said workface having a radius of curvature generated about an axis arranged belowsaid second mentioned axis, and means for raising the rear end of saidbody member relative to said supi ort. P 2. A holder for a workpiece,comprising a base on which said workpiece is adapted to be placed, and apair of clamping devices mounted on said base and adapted to be arrangedone on each of opposite sides of said workpiece, each of said clampingdevices comprising a support arranged for immovable connection to saidbase, a body member pivotally mounted on said support about a transverseaxis arranged adjacent its front end, a jaw member having a curved workface at its front end adapted to engage said workpiece and pivotallymounted on said body member about a transverse axis arranged above andin rear of said first mentioned axis, said work face having a radius ofcurvature generated about an axis arranged below said second mentionedaxis, spring means operatively arranged to urge the front ends of saidjaw and body members apart, stop means limiting the separation of saidfront ends, and means for raising the rear end of said body memberrelative to said support.

3. A holder as set forth in claim 2 in which said last means comprises ajack screw arranged in a threaded hole in the rear portion of said bodymember and bearing against said support.

4. A holder as set forth in claim 2 in which said stop means comprise atransverse pin carried by one of said jaw and body members and extendinginto an enlarged hole in the other of said members.

5. A holder as set forth in claim 2 in which said stop means compriseoverlapping surfaces on said jaw and body members.

6. In a holder for a workpiece, a clamping device comprising a supportfixed relative to said workpiece, a body member pivotally mounted at oneend to said support, a jaw member pivotally mounted on said body memberon an axis parallel to and remote from said first mentioned axis, saidjaw member having a curved work face generated about an axis parallel toand arranged below 'said second mentioned axis, and means for turningsaid body member about said rst mentioned axis relative to said support.

7. In a holder for a workpiece, the combination comprising an elongatedbase having generally a channel shape in cross section, and a clampingdevice arranged longitudinally adjustably on said base and including asupport having a series of longitudinally and uniformly spaced holes,said base having a series of longitudinally and uniformly `spaced holes,one of said series of holes being spaced farther apart than in theother, and a locking pin adapted to be inserted in holes of both saidseries when alined.

8. In a holder for a workpiece, the combination comprising an elongatedbase having generally a channel shape in cross section and also havingopposing longitudinal grooves on the inside of the side walls thereof,and a clamping device arranged longitudinally adjustably on lsaid baseand including a slide arranged in said grooves and having a series oflongitudinally and uniformly spaced holes extending transverselytherethrough, said side walls of said base having a series oflongitudinally and uniformly spaced transverse holes therein, one ofsaid series of holes being spaced farther apart than in the other, and alocking pin adapted to be inserted in holes of both said series whenalined.

9. In a holder for a workpiece, the combination comprising an elongatedbase having generally a channel shape in cross section and also havinglongitudinal grooves on the outside of the side walls thereof, and aclamping device arranged longitudinally adjustably on said base andincluding a support having generally an inverted channel shape in crosssection and inturned flanges at its lower end adapted to be received insaid grooves, said support also having a series of longitudinally anduniformly spaced vertical holes therein extending through said liangesthereof, said side walls of said base having a series of longitudinallyand uniformly spaced vertical holes therein, one of said series of holesbeing spaced farther apart than in the other, and a locking pin adaptedto be inserted in holes of both said series when alined.

10. In a holder for a workpiece, the combination comprising an elongatedbase having generally a channel shape in cross section and also havingon the outside of each side wall thereof two series of crossed grooveseach inclined to the vertical, and a clamping device arrangedlongitudinally adjustably on said base and including a support havinggenerally an inverted channel shape in cross section and depending sidewalls embracing said irst mentioned side walls and a series of ribsarranged on the inside of said depending side walls and adapted toengage with one or the other of said series of grooves.

References Cited in the tile of this patent UNITED STATES PATENTS1,457,307 Kerns June 5, 1923 1,546,062 Edmunds July 14, 1925 FOREIGNPATENTS 904,373 Germany May 24, 1954 OTHER REFERENCES AmericanMachinist, April 10, 1947, page 139.

